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71.
Amaral JS Casal S Alves MR Seabra RM Oliveira BP 《Journal of agricultural and food chemistry》2006,54(4):1329-1336
Hazelnuts from 19 cultivars collected during 3 consecutive-year crops, in 2 different geographical localities, for a total of 79 samples, were evaluated for their contents in tocopherols and tocotrienols by normal-phase high-performance liquid chromatography coupled to a series arrangement of a diode array and a fluorescence detector. Seven compounds were identified and quantified. All samples presented alpha-, beta-, gamma-, and delta- tocopherols and beta-tocotrienol; alpha- and gamma-tocotrienols were detected in some of the studied samples. alpha-Tocopherol was the major compound in all samples, ranging from 105.9 to 226.8 mg/kg of hazelnut. Considering the generality of the obtained results, an identical qualitative and quantitative pattern was found, which can define a chemical fingerprint that may be helpful in the assessment of identity and quality of hazelnut oils. Statistical analyses were carried out in order to check for differences among cultivars, year crops, and geographical localities. Although some differences were observed when different-year crops and geographical localities were considered, neither of these factors seemed to produce considerable differences in terms of tocopherol and tocotrienol contents. Some minor differences were observed among cultivars. 相似文献
72.
Areias F Valentão P Andrade PB Ferreres F Seabra RM 《Journal of agricultural and food chemistry》2000,48(12):6081-6084
A reversed-phase high-performance liquid chromatography/diode-array detector procedure is proposed for the determination of six phenolic compounds (caffeic acid, luteolin 7-O-glucoside, rosmarinic acid, apigenin, hispidulin, and cirsimaritin) in sage. The chromatographic separation was achieved using a reversed-phase Spherisorb ODS2 (5-microm particle size, 25.0 x 0.46 cm) column. Of the several extractive solvents assayed only ethyl ether, ethyl acetate, and acetone were able to extract all the compounds mentioned. Best resolution was obtained using a gradient of water/phosphoric acid (999:1) and acetonitrile. Ten samples cultivated in two experimental fields (1997-1999) were analyzed and the individual compounds quantified. Four commercially available samples were also analyzed and the results are discussed. 相似文献
73.
Quantitation of nine organic acids in wild mushrooms 总被引:3,自引:0,他引:3
Valentão P Lopes G Valente M Barbosa P Andrade PB Silva BM Baptista P Seabra RM 《Journal of agricultural and food chemistry》2005,53(9):3626-3630
The organic acids composition of six wild edible mushroom species (Amanita caesarea, Boletus edulis, Gyroporus castaneus, Lactarius deliciosus, Suillus collinitus, and Xerocomus chrysenteron) was determined by an HPLC-UV detector method. The results showed that all of the samples presented a profile composed of at least five organic acids: citric, ketoglutaric, malic, succinic, and fumaric acids. Several samples also contained oxalic, ascorbic, quinic, and shikimic acids. In a general way, the quantitation of the identified compounds indicated that malic acid, followed by the pair citric plus ketoglutaric acids, were the main compounds in the analyzed species, with the exception of A. caesarea, in which malic and ascorbic acids were the most abundant compounds. The relative amounts and the presence/absence of each identified compound may be useful for the differentiation of the species. 相似文献
74.
Silva BM Andrade PB Valentão P Ferreres F Seabra RM Ferreira MA 《Journal of agricultural and food chemistry》2004,52(15):4705-4712
To study the antioxidant activity of quince fruit (pulp, peel, and seed) and jam, methanolic extracts were prepared. Each extract was fractionated into a phenolic fraction and an organic acid fraction and was analyzed by high-performance liquid chromatography (HPLC)/diode array detection and HPLC/UV, respectively. Antiradical activities of the extracts and fractions were evaluated by a microassay using 1,1'-diphenyl-2-picrylhydrazyl. The phenolic fraction always exhibited a stronger antioxidant activity than the whole methanolic extract. Organic acid extracts were always the weakest in terms of antiradical activity, which seems to indicate that the phenolic fraction gives a higher contribution for the antioxidant potential of quince fruit and jam. The evaluation of the antioxidant activity of methanolic extracts showed that peel extract was the one presenting the highest antioxidant capacity. The IC50 values of quince pulp, peel, and jam extracts were correlated with the caffeoylquinic acids total content. Among the phenolic fractions, the seed extract was the one that exhibited the strongest antioxidant activity. The IC50 values of quince pulp, peel, and jam phenolic extracts were strongly correlated with caffeoylquinic acids and phenolics total contents. For organic acid fractions, the peel extract was the one that had the strongest antiradical activity. The IC50 values of quince pulp, peel, and jam organic acid fractions were correlated with the ascorbic acid and citric acid contents. 相似文献
75.
76.
The possible adaptive advantages of terrestrial egg deposition in some fluvial diadromous galaxiid fishes (Teleostei: Galaxiidae) 总被引:1,自引:0,他引:1
Several diadromous New Zealand and Australian species of Galaxias are now known, or suspected, to deposit their eggs amongst riparian vegetation or substrates either supratidally in estuaries or in forested streams in locations that are only temporarily submerged by elevated water levels. The eggs develop in a humid atmosphere and hatch when the egg deposition sites are resubmerged; a significant role for agitation in stimulating hatching seeming likely. There are risks from the eggs becoming dehydrated, and also from a failure by water to resubmerge the eggs before they have exhausted their energy resources. Hatching is triggered by elevated flows, perhaps being an outcome of agitation of the eggs. Elevated flows may also increase the rate of downstream transport of the larvae, facilitating survival during dispersal to sea from spawning sites in streams that may be long distances inland. Hatching during flood events may favour survival of the larvae because turbid flows may provide ‘cover’ for the larvae as they emigrate to sea. Risks from egg predation by aquatic predators may be replaced by risks from terrestrial predators. 相似文献
77.
The objectives of the present study were to determine ionic and organic composition of seminal plasma, sperm concentration and their relationships in the Persian sturgeon (Acipenser persicus). In this regard, ionic content (Na+, K+, Cl?, Ca2+ and Mg2+) and organic content (total protein, glucose, cholesterol and triglyceride) along with sperm concentration were measured in 17 specimens of the Persian sturgeon. The seminal plasma contained 59.53 ± 2.56 mm /l sodium, 9.1 ± 1.42 mm chloride, 4.72 ± 0.3 mm potassium, 1.45 ± 0.075 mm calcium and 0.7 ± 0.072 mm magnesium. The following organic contents were found: total protein 0.11 ± 0.02 g/dl, glucose 22.18 ± 4.16 mg/dl, cholesterol 6.67 ± 1.04 mg/dl and triglyceride 15.2 ± 0.65 mg/dl. The mean sperm concentration was estimated to be 1.6 ± 0.12 (×109 sperm/ml). A significant relationship was found between sperm concentration and K+ of seminal plasma (r = 0.533, p < 0.05). Significant correlations were observed between ionic contents: Na+ vs Cl? (r = ?0.854, p < 0.01) and Mg2+ vs K+ (?0.583, p < 0.05). Also, level of triglyceride was negatively correlated with Mg2+ (r = ?0.503, p < 0.05). Presented data could be considered as a complementary study for developing special extenders and protectant solutions for improving artificial fertilization in this valuable species. 相似文献
78.
MA Lee TR Manley BC Glass RM Anderson SJ Wilson JS O'Keefe 《New Zealand veterinary journal》2013,61(5):222-227
AIM: To use an established high through-put genotyping procedure to gain an estimate of the frequency of alleles of the prion protein (PrP) gene in some common sheep breeds in New Zealand. METHODS: Using a genotyping procedure based on matrix-assisted laser desorption ionisation-time of flight (MALDI-TOF), DNA samples from 3,024 sheep from New Zealand, including breeds such as Romney, Texel, Coopworth, Merino and mixedbreed, were isolated, genotyped and the results analysed. RESULTS: The 15 scrapie genotypes commonly reported, and derived from the five commonly reported allelic variants (ARR, ARQ, AHQ, ARH and VRQ), were all observed in the samples analysed. The estimates were indicative of the frequencies in the population of alleles present in breeds of sheep in New Zealand. There was a significant difference between the frequencies of alleles between breeds, but the ARQ, followed by the ARR allele, were, except in Carwell sheep, the most common alleles present. CONCLUSION: This study gave an indication of the percentages of PrP gene alleles in sheep in New Zealand, including data previously unreported from breeds in this country. It is of interest because of the relatively large size of the sheep population in New Zealand compared with many countries, and it provides some useful information on the genetic susceptibility or resistance of the sheep population in New Zealand to scrapie. The frequencies of the alleles can be different for an individual breed compared between countries. 相似文献
79.
A. Catarina Guedes Maria S. Gi?o Rui Seabra A. C. Silva Ferreira Paula Tamagnini Pedro Moradas-Ferreira F. Xavier Malcata 《Marine drugs》2013,11(4):1256-1270
A growing market for novel antioxidants obtained from non-expensive sources justifies educated screening of microalgae for their potential antioxidant features. Characterization of the antioxidant profile of 18 species of cyanobacteria (prokaryotic microalgae) and 23 species of (eukaryotic) microalgae is accordingly reported in this paper. The total antioxidant capacity, accounted for by both water- and lipid-soluble antioxidants, was evaluated by the (radical cation) ABTS method. For complementary characterization of cell extracts, a deoxyribose assay was carried out, as well as a bacteriophage P22/Salmonella-mediated approach. The microalga Scenedesmus obliquus strain M2-1 exhibited the highest (p > 0.05) total antioxidant capacity (149 ± 47 AAU) of intracellular extracts. Its scavenger activity correlated well with its protective effects against DNA oxidative damage induced by copper(II)-ascorbic acid; and against decay in bacteriophage infection capacity induced by H2O2. Finally, performance of an Ames test revealed no mutagenic effects of the said extract. 相似文献
80.
Abstract CASE HISTORY:?A 3-month-old female Warmblood foal was presented after displaying signs of colic with pyrexia for 5 days. CLINICAL AND PATHOLOGICAL FINDINGS:?The foal continued to show signs of colic, frequently passed urine, and was pyrexic with an elevated white blood cell count. The umbilical stalk was thickened but there was no evidence of purulent material. Exploratory laparotomy revealed an enlarged left umbilical artery remnant tightly adhered to the bladder wall. The left umbilical artery continued to an aneurysm involving the distal aorta. The foal was subject to euthanasia and post-mortem examination confirmed a spherical aortic aneurysm, in the dorsal midline caudal to the kidneys that contained a large thrombus. Histopathological examination revealed inflammation and necrosis of the tunica intima and tunica media of the left umbilical artery with suppuration and bacterial colonies evident in the periarterial tissues. DIAGNOSIS:?Infected aortic aneurysm presumably caused by an umbilical artery infection. CLINICAL RELEVANCE:?A previously undetected umbilical infection appears to have resulted in an unusual delayed complication causing signs of colic in a foal. Veterinarians should be aware of this condition, and the possibility that it may be a cause of signs of colic in foals. Diagnosis based on ultrasonography should be possible, but may require sedation, visceral analgesia and careful examination. 相似文献